Morgause

In the early chronicles and romances based on or inspired by Geoffrey of Monmouth, as well as in the Welsh tradition, her figure and role are commonly that of Gawain's mother, and she is either a full or half sister to Arthur.

The corresponding character in Geoffrey of Monmouth's early-12th-century Norman-Welsh chronicle Historia Regum Britanniae is named Anna, who is depicted as the sole daughter of Uther Pendragon and his wife Igraine, thus making her Arthur's full (younger) sister.

This was later elaborated in the romance De Ortu Waluuanii, telling how the teenage Lot fell in mutual love with the also young Anna while serving as her page when he was a royal hostage at the court of Uther.

[9] The Birth of Arthur further gives Anna her first husband, Emyr Llydaw (Budic II of Brittany), king of Armorica, by whom she is the mother of Howel (Hoel),[10] and furthermore gives her three daughters by Lleu in addition to the sons Gwalchmei and Medrawd (Mordred).

Medievalist Roger Sherman Loomis suggested that this toponym was corrupted first into the variants of "Morcades" and finally into "Morgause" due to the influence of the name "Morgan",[12] and also derived her figure from that of the Welsh mythology's humanised goddess Dechtire.

Her version in the vast prose romance Vulgate Cycle from the early 13th century is named Brimesent (with manuscript variant Hermesent), who in turn is called Belisent in the late 13th-century Arthour and Merlin and Albagia in the 15th-century Italian compilation La Tavola Ritonda.

Thomas Malory's 1485 compilation of Arthurian legends Le Morte d'Arthur, based largely on French prose cycles, Morgause (also Morgawse or Margawse) is one of three daughters born to Duke Gorlois and Lady Igraine.

Afterwards, she and her younger sisters, Elaine (called Blasine in Merlin) and Morgan ("le Fay", later the mother of Yvain), now Uther's foster daughters, are married off to allies or vassals of their stepfather.

All of her sons depart their father's court to take service at Camelot, where Gawain and Gaheris avenge Lot's death by killing Pellinore, thereby launching a long blood feud between the two families that contributes to bringing the ruin to Arthur's kingdom.

Enraged, he grabs Morgause by her hair and swiftly beheads her, but spares her unarmed lover (who is left naked in bed covered in her blood and is killed later by four Orkney brothers in an unequal fight).

Gaheris (who in the Post-Vulgate version defends his act as a just punishment of the queen for her "wretched debauchery"[14]) is consequently banished from the court of Arthur (though he reappears later in the narrative, eventually being slain by Lancelot during the rescue of Guinevere).

In the Post-Vulgate story, Gaheris' brothers Gawain and Agravain initially vow to kill him in revenge for their mother's death until they are persuaded by Gareth and Bors to end the bloodshed in the family.

In the Vulgate Merlin, the episode takes place earlier, back when a young teenage Arthur was only a mere squire to his foster-brother Kay (prior to the fateful drawing of the sword in the stone) and completely oblivious about his true heritage.

During a meeting of the lords of Britain, when King Lot is out hunting, Arthur sneaks into the queen's chamber and pretends to be her husband; she eventually discovers the deception but forgives him the next morning and agrees to keep the incident a secret between the two of them.